I'm working on a 1937 Ford car radio, model F-1442 and my manual for the radio does not seem to have any instructions for alignment. I need to know where to hook up the signal generator to align the radio. I can hear static through the speaker but so far no radio signals at all and I have been working replacing the old wax paper capacitors. I need to know which tube, and what pin I connect to, I am going to guess the number 78 tube at 260 KC but I want to verify that.